AngularJS + d3js: Issues with resizing objects - javascript

I'm attempting to integrate AngularJS with d3 for dragging and resizing. I've managed to create a rect object that is draggable in an SVG element, and resizable using resize handles. The resize handles work as they should, but resizing is choppy when I try to resize in the north or east direction. I created the following Plunk as a demo of the issue: http://plnkr.co/tG19vpyyw0OHMetLOu2U. (I've simplified it to show the issue I've run into, so there's only one resize handle.)
Dragging works as it should, and resizing in the west and south directions works as well (not shown in the demo).
Figured I'd ask the community and see if anyone had run into this before. Thank you all.

The problem is that you're modifying the rect element itself and the enclosing g element. There's a very short delay between setting the size of the rect and the position of the g simply because this has to be done with two separate commands. During this delay, the cursor position relative the the drag rectangle changes, firing a new drag event with values that correspond to the inconsistent intermediate state. This is fixed immediately afterwards (as soon as the attributes of both elements have been adjusted) and a new drag event is fired that fixes the inconsistency, but it is noticeable as a flicker.
The easiest way to fix this is to change both size and position for the rect and nothing for the g element. This means adjusting the position of the drag rectangle as well and makes the code less nice, but avoids the timing/inconsistency problem.
So myrect becomes
var myRect = d3.select(document.createElementNS("http://www.w3.org/2000/svg", "rect"))
.attr("data-ng-width", "{{square.w}}")
.attr("data-ng-height", "{{square.h}}")
.attr("stroke", "yellow")
.attr("stroke-width", 3)
.attr("fill-opacity", 0)
.attr("data-ng-x", "{{square.x}}")
.attr("data-ng-y", "{{square.y}}");
and resizer
var resizer = myGroup.append("rect")
.attr("width", 5)
.attr("height", 5)
.attr("stroke", "blue")
.attr("stroke-width", 1)
.attr("fill-opacity", 0)
.attr("cursor", "nw-resize")
.attr("x", "{{square.x-2.5}}")
.attr("y", "{{square.y-2.5}}")
.call(nresize);
I've updated your code with this solution here.

Related

How to define the node entering position in D3 js force layout

I am trying to implement a radial force layout in D3.js , I saw a similar example but i am stuck on how to initiate the node positions in the layout.
http://bl.ocks.org/vlandham/5087480
Thanks in Advance
Initialising a position is just done by setting the cx and cy positions. The most logical place is where the radius is currently being set i.e.
.attr("r", 10)
.attr("cx", 5) //added
.attr("cy", 5) //added
Of course, you can do something more exotic if you are using the bound data to initialise position.
This will only set the starting point though - the force layout will then take over and position elements. The advantage is that you can potentially reduce some of the initial node movement if you get it right.

Zooming issues with Force Directed

I've generated a D3 visualization (a force directed graph) that requires zooming and panning. I've got 2 problems however when it comes to zooming, and I can't find any decent examples on how I might overcome these problems:
The first problem is I've followed all the examples I can find about zooming, which involves adding groupings and adding a rectangle to ensure that the entire area is zoomeable. If I style the rectangle a slightly opaque blue then I get SVG that looks like this when I zoom out:
The problem with this is that I can zoom in/out absolutely fine while I've got my mouse over the blue rectangle area. The problem is I want this to be fully opaque, which means that when I zoom right out, it's very easy to place the cursor outside of this box and then you're unable to zoom in. Is there a way I can make the SVG itself zoomeable or pick up on these events?
This is how I go about generating the various layers and the zoomed function:
function zoomed() {
group2.attr("transform", "translate(" + d3.event.translate + ")scale(" + d3.event.scale + ")");
}
svg = d3.select(target)
.attr("pointer-events", "all")
.append("svg");
group = svg.append('svg:g')
.call(d3.behavior.zoom().on('zoom', zoomed))
.on("dblclick.zoom", null);
group2 = group.append("g");
rect = group2.append('svg:rect')
.style("opacity", 0.3)
.attr('width', width)
.attr('height', height);
The second problem I have is that I'm trying to automatically size my text based on this http://bl.ocks.org/mbostock/1846692 example. When I've tried this however I seem to be getting text that renders really poorly. It seems to suffer from:
Being difficult to read
Not appearing contained within the circle
Being so small the entire thing compresses (image 2)
var texts = planets.append("text")
.text(function(d) { return d.name; })
.style("font-size", "24px") // initial guess
.style("font-size", function(d) {
return Math.min( 2 * d.size, (2 * d.size - 8) / this.getComputedTextLength() * 24) + "px";
})
.attr("dx", function(d) { return -d.size; })
.attr("dy", ".35em")
.style("fill", "white");
I thought that SVG would just handle this, I understand that some of the font-sizes can come out small, but if you zoom in should that not all sort itself out?
I've got a JSFiddle http://jsfiddle.net/IPWright83/vo7Lpefs/22/ to demonstrate.
I've not yet managed to work out a resolution to my first issue (regarding the zooming box) however I did manage to track down the text rendering issue.
This was actually because the each circle/node had a stroke property to provide the white border. This was also applying to the text element, and when the font was very small the stroke was much larger than the overall fill of the text. Removing the stroke from the text elements ensured that they rendered even when very small.

d3 SVG Transitions Not Always Ending At Required Value

I have a d3 visualisation on a web page that shows a collection of plot points on a chart.
It's all very simple really with just two axis and sometimes maybe 30 points to plot. As I render these plots I perform a transition on the r attributes of the SVG circles. The code that does this is:
g.append("svg:circle")
.attr("class", "plot-circle")
.attr("cx", xCo)
.attr("cy", yCo)
.attr("r", 0)
.transition()
.delay(function() { return delayInput * 100; })
.duration(plotExplosionDuration)
.ease(Math.sqrt)
.attr("r", 6);
All that occurs is that the circles are initially set to r=0 which means they aren't rendered at all. Then I start a transition on the appended circle to take this radius up to 6.
The problem is that it appears on some machines these transitions don't stop at r=6 and some plots end up being much bigger than the value set after the transition.
I simply cannot duplicate this on my main development machine (PC), my iPad nor my MacBook Pro which leads me to think it might be performance or machine load causing this?
has anyone got any ideas on how to ensure the transition stops at the defined final r value?

Implementing <div> tooltips via d3 within an <svg> container

I'm relatively new to D3, svg, and javascript in general, so please bear with me :]
I have been experimenting with D3 for creating plots and graphs. I have created a small plot using D3 and have been attempting to make it compatible with IE8. Here is a link to the more-or-less working build of my graph.
http://jsfiddle.net/kingernest/YDQR4/1/
After some research, I quickly realized that the only way running D3 on IE8 would be at all feasible is by using other APIs in conjunction with D3. Luckily, I found that someone had already put in some work into a project called "r2d3" which, from my understanding, uses raphael to paint the canvas on the IE8 window instead of using SVG (which apparenly was not supported in IE8).
I have been able to get items drawn on the screen, which is half the battle. However, I'm having many issues, particularly with my tooltip. My tooltip is written as a DIV container that floats and changes position/opacity on hover of the data circles. This seems to work fine in other browsers, but with r2d3, I have not been able to get it working. I suspect this is because of the fact that I am creating the div tooltip outside of the (in the #main div). However, I have tried placing tooltips inside of the SVG container with no avail. I then did more reseach and discovered I would have to wrap a div container inside a tag, but after some experimentation with this, I still wasn't able to get the tooltip to work correctly in IE. I attempted to wrap the in a SVG group (), and altered the positioning of this object instead, but this did not seem to work either, and simply through numerous exceptions when trying to append the foreignObject tag to a group.
At this point I'm sort of stuck, and was wondering if anyone had any suggestions as to how I may be able to successfully implement the tooltips. I've also noticed that using d3.select(this) inside my functions, when attempting to select a particular data point (in this case, a circle) seems to present a number of issues when attempting to access or modify that item's attributes, but I think this is a whole other issue entirely.
Any help is greatly appreciated!
Example of how I'm currently creating the tooltips:
//Create tooltip element
var tooltip = d3.select("#main")
.append("div")
.attr("class", "tooltip")
.style("position", "absolute")
.style("z-index", "10")
.style("opacity", 0);
function mousemove()
{ //Move tooltip to mouse location
return tooltip.style("top", (event.pageY-10)+"px").style("left",(event.pageX+10)+"px");
}
//Mouseover function for circles, displays shortened tooltip and causes other circles to become opaque
function mouseover()
{
var myCircle = d3.select(this);
d3.select(this).attr("class", "dataCircleSelected"); //Color circle green
tooltip.html( //Populate tooltip text
"Username: " + d3.select(this).attr("username") + "<br/>" +
"Session ID: " + d3.select(this).attr("sessionid") + "<br/>" +
"Impact CPU: " + d3.select(this).attr("impact")
)
.transition()
.duration(250)
.style("opacity", .7);
//After 1000ms, make other circle opaque
svg.selectAll("circle")
.filter(function(d, i){ //return every other circle
return !d.compare(myCircle[0][0].__data__);
})
.transition().delay(1000)
.style("opacity", .2);
}
Have you tried using foreignObjects AND explicitly using the xhtml namespace for html tags in the foreignObject (write xhtml:div instead of div) as explained here: HTML element inside SVG not displayed ?
This would give something like that for the tooltip definition
var tooltip = d3.select("#main").append("foreignObject")
.append("xhtml:div")
.attr("class", "tooltip")
.style("position", "absolute")
.style("z-index", "10")
.style("opacity", 0);

Zoom event overrides Drag behavior in d3js

I'm trying to implement both dragging and zooming event handlers for a circle item using d3js. I've added behaviors for both events as given below
var circle = svg.append("circle")
.attr("fill", "green")
.attr("opacity", 0.6)
.attr("cx", 100)
.attr("cy", 100)
.attr("r", 13)
.call(d3.behavior.drag().on("drag", drag))
.call(d3.behavior.zoom().on("zoom", zoom));
without zooming the object, dragging works fine. after zooming in/out of the object, dragging does not work, yet all events containing a mousedown is caught as "zoom" event.
For full source please see http://jsfiddle.net/xTaDC/
Seems that i did not understand the "d3.behavior". https://github.com/mbostock/d3/blob/master/examples/mercator/mercator-zoom-constrained.html provides only zoom handler and handles both dragging and zooming.
What am i doing wrong here?
As far as I know, d3's zoom behavior already handles dragging, so the drag thing is redundant. Try making use of the zoom's d3.event.translate (which is a 2 element array, so if you want to get the x value only, you can go d3.event.translate[0]) to replicate the functionality in your Drag into your Zoom.
Additional tip: To make things easier on yourself, make sure that you apply your call(zoom) on the parent of whatever it is that you're trying to drag. This will prevent jittery and shaky behavior.
Source is of course, the d3 wiki.
"This behavior automatically creates event listeners to handle zooming and panning gestures on a container element. Both mouse and touch events are supported."
https://github.com/mbostock/d3/wiki/Zoom-Behavior
I faced similar problem and solved it by overriding other sub events of zoom.
Add below code after zoom and drag event listeners
.on("mousedown.zoom", null)
.on("touchstart.zoom", null)
.on("touchmove.zoom", null)
.on("touchend.zoom", null);
So the full code will look like
var circle = svg.append("circle")
.attr("fill", "green")
.attr("opacity", 0.6)
.attr("cx", 100)
.attr("cy", 100)
.attr("r", 13)
.call(d3.behavior.drag().on("drag", drag))
.call(d3.behavior.zoom().on("zoom", zoom))
.on("mousedown.zoom", null)
.on("touchstart.zoom", null)
.on("touchmove.zoom", null)
.on("touchend.zoom", null);
Append your graph with sensitive event area (must be the last append) :
var rect = svg.append("svg:rect")
.attr("class", "pane")
.attr("width", w)
.attr("height", h);
AFTER (not include) add event management on this area
rect.call(d3.behavior.zoom().x(x).scaleExtent([0.5, 4]).on("zoom", draw));
and the draw function is
function draw() {
svg.select("g.x.axis").call(xAxis);
svg.select("g.y.axis").call(yAxis);
svg.select("path.area").attr("d", area);
svg.select("path.line").attr("d", line);
}
see this exemple : https://groups.google.com/forum/?fromgroups=#!topic/d3-js/6p7Lbnz-jRQ%5B1-25-false%5D
In 2020, use d3.zoom to enable zooming and panning: https://observablehq.com/#d3/zoom
If you want to enable panning for the background, while allowing to drag the circle, see the official example where d3.drag and d3.zoom are used on different elements: https://observablehq.com/#d3/drag-zoom

Categories

Resources